Scanning probe lithography (SPL) describes a set of nanolithographic methods to pattern material on the

nanoscale The nanoscopic scale (or nanoscale) usually refers to structures with a length scale applicable to nanotechnology, usually cited as 1–100 nanometers (nm). A nanometer is a billionth of a meter. The nanoscopic scale is (roughly speaking) a lo ...

using scanning probes. It is a direct-write, mask-less approach which bypasses the

diffraction limit The resolution of an optical imaging system a microscope, telescope, or camera can be limited by factors such as imperfections in the lenses or misalignment. However, there is a principal limit to the resolution of any optical system, due to t ...

and can reach resolutions below 10 nm. It is considered an alternative lithographic technology often used in academic and research environments. The term ''scanning probe lithography'' was coined after the first patterning experiments with

scanning probe microscope Scan may refer to: Acronyms * Schedules for Clinical Assessment in Neuropsychiatry (SCAN), a psychiatric diagnostic tool developed by WHO * Shared Check Authorization Network (SCAN), a database of bad check writers and collection agency for bad ...

s (SPM) in the late 1980s.

Classification

The different approaches towards SPL can be classified by their goal to either add or remove material, by the general nature of the process either chemical or physical, or according to the driving mechanisms of the probe-surface interaction used in the patterning process:

mechanical Mechanical may refer to: Machine * Machine (mechanical), a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement * Mechanical calculator, a device used to perform the basic operations of ...

thermal A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example ...

, diffusive and

electrical Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described ...

Overview

Mechanical/thermo-mechanical

Mechanical scanning probe lithography (m-SPL) is a nanomachining or ''nano-scratching''

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approach without the application of heat. Thermo-mechanical SPL applies heat together with a mechanical force, e.g. indenting of polymers in the

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Thermal

Thermal scanning probe lithography (t-SPL) uses a heatable scanning probe in order to efficiently remove material from a surface without the application of significant mechanical forces. The patterning depth can be controlled to create high-resolution 3D structures.

Thermo-chemical

Thermochemical scanning probe lithography (tc-SPL) or ''thermochemical nanolithography'' (TCNL) employs the scanning probe tips to induce thermally activated chemical reactions to change the chemical

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or the

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of surfaces. Such thermally activated reactions have been shown in

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

organic semiconductor Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals or ...

electroluminescent Electroluminescence (EL) is an optical and electrical phenomenon, in which a material emits light in response to the passage of an electric current or to a strong electric field. This is distinct from black body light emission resulting from ...

conjugated polymers, and

nanoribbon Nanoribbon may refer to: * Graphene nanoribbons * Silicene nanoribbons * Boron nitride nanoribbons * Gallium(III) oxide nanoribbons * titanate nanoribbons - see titanium dioxide * Phosphorene nanoribbons {{Short pages monitor